Metrographical table



y 22, 1951 F. ELIAS-REYES 2,553,705

METROGRAPHI CAL TABLE Filed April 5, 1948 I be 23 /4 l9 2 INVENTO.

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ATTD R N EYS Patented May 22, 1951 UNITED STATES PATENT OFFICE METROGRAPHICAL TABLE Francisco Elias-Reyes, San Salvador, El Salvador Application April 5, 1948, Serial No. 19,132

1Claim. 1

This invention relates to a metrographical table.

It is an object of the present invention to provide a metrographical table adapted for use in the making of geometrical and industrial drawings wherein the paper can be extended readily upon the same without the use of thumb tacks and wherein the data is provided upon the board and beneath the paper from which angles may be easily drawn and whereby the necessity for a T square to effect the drawing operations is eliminated.

Other objects of the present invention are to provide a metrographical table for drawing boards which is of simple construction, inexpensive to manufacture, and eificient in operation.

For other objects and for a better understanding of the invention, reference may be had to the following detailed description taken in connection with the accompanying drawing, in which Fig. 1 is a top plan view of the table or board embodying the features of the present invention.

Fig. 2 is an enlarged sectional view taken on line 22 of Fig. 1.

Fig. 3 is an enlarged sectional view taken on line 33 of Fig. l.

Referring now to the figures, 10 represents board material which may be preferably of plywood and of sufficient thickness to provide for a rigid drawing board. The top and bottom edges of the board are recessed on the respective opposite sides as indicated at H and I2 to receive paper retaining members or clamping plates l3 which-are hinged as indicated at [4 to the edges of the board by means of hinges l5 and when raised the paper can be extended under the same. The bottom faces of the members I3 are serrated to make for good engagement with the paper.

Over the surfaces of the board there are extended thin plastic sheets [6 which may have sets of lines painted thereon as shown in Fig. 1 and which can be used instead of triangles or other drafting instruments to effect the drawing or sketch being made on the paper sheet.

These lines can extend vertically and horizontally in a graph-like manner or can be extended to a center ll or both kinds of lines being provided on the sheet. The plastic sheet on the reverse side of the board may be differently lined depending upon the use to which the board is to be put.

The hinges l5 are secured to the edge faces of the board by screws [9. The clamping members l3 are held in engagement with the paper by leaf springs 2| and 22 which are extended into a slot 23 with an edge member 24 of T section. The member has flange portions 25 which extend along the rear edges of the members I3. To insert the paper, the members [3 are depressed and raised to adotted line position as indicated at 26.

On the side edges of the board, there can be provided an opening 2'! into which can be ex- Number tended a drawer 28 having a front face 29 and finger gripping recesses 3| may be provided in the upper and lower surfaces of the board to facilitate removing the drawer.

In addition to providing lines on the plastic sheets indicia may also be placed on the lateral margins of the board and on the members [3. The plastic sheets [6 may also have irregular lines and mathematical data thereon to facilitate use thereof with graphs or in making different mathematical calculations.

While Various changes may be made in the detail construction, it shall be understood that such changes shall be within the spirit and scope of the present invention as defined by the appended claim.

I claim:

In a metrographical table, the combination which comprises a rectangular shaped board having longitudinally disposed and transverse sides providing a table top, said longitudinally disposed sides having continuous flat recesses in the edges of both surfaces and continuous centrally disposed grooves positioned midway between the said side surfaces thereof, continuous clamping plates positioned inthe recesses of the sides of the board and extended from the board, hinges secured to the inner surfaces of the plates and edges of the board pivotally mounting the plates on the board, T-shaped edge members having tongues with perpendicularly disposed flanges on the outer edges carried by the longitudinally disposed sides of the board with the tongues positioned in the grooves and with the edges of the flanges in engagement with the outer extending edges of the clamping plates, and springs also mounted in the said grooves in the longitudinally disposed sides of the board and having arcuate extended ends positioned to engage the inner surfaces of the extended ends of the clamping plates to resiliently urge the sections of said plates in the recesses into gripping relation with paper positioned with the edges thereof in the said recesses, the inner surfaces of the sections of said plates positioned in the recesses being serrated to facilitate gripping the paper.

F. ELIAS-REYES.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Name Date Nigra Jan. 16, 1940 Stenquist June 4, 1940 Leffel Aug. 31, 1943 FOREIGN PATENTS Country Date Austria Apr. 10, 1902 Germany Jan. 26, 1918 Number 

